This invention relates to methods and apparatus for accessing the pericardial space for medical treatment of the heart.
Knowledge of the pericardium dates back to the time of Galen (129-200 A.D.) the Greek physician and anatomist who gave the pericardium its name. The pericardial sac surrounds the heart like a glove enfolds a hand, and the pericardial space is naturally fluid-filled. The normal pericardium functions to prevent dilatation of the chambers of the heart, lubricates the surfaces of the heart, and maintains the heart in a fixed geometric position. It also provides a barrier to the spread of infection from adjacent structures in the chest, and prevents the adhesion of surrounding tissues to the heart. See generally, Holt J P: The normal pericardium, Amer J Cardiol 26:455,1970; Spodick D H: Medical history of the pericardium, Amer J Cardiol 26:447,1970. The normal pericardial space is small in volume and the fluid film within it is too thin to functionally separate the heart from the pericardium. It has been observed that when fluid is injected into the pericardial space it accumulates in the atrioventricular and interventricular grooves, but not over the ventricular surfaces [Shabetai R: Pericardial and cardiac pressure, Circulation 77.1, 1988].
Pericardiocentesis, or puncture of the pericardium, heretofore has been indicated for (1) diagnosis of pericardial disease(s) by study of the pericardial fluid, (2) withdrawal of pericardial fluid for the treatment of acute cardiac tamponade, and (3) infusion of therapeutic agents for the treatment of malignant effusion or tumors. During 1994, it is estimated that approximately 12,000 pericardiocentesis procedures were performed in the United States and that less than 200 of these patients underwent therapy with the intrapericardial injection of drugs. At present, intrapericardial injection of drugs is clinically limited to the treatment of abnormal pericardial conditions and diseases, such as malignant or loculated pericardial effusions and tumors. Drugs that have been injected into the pericardial space include antibiotic (sclerosing) agents [Wei J, et al: Recurrent cardiac tamponade and large pericardial effusions: Management with an indwelling pericardial catheter, Amer J Cardiol 42:281,1978; Davis S, et al: Intrapericardial tetracycline for the management of cardiac tamponade secondary to malignant pericardial effusion, N Engl J Med 299:1113,1978; Shepherd F, et al: Tetracycline sclerosis in the management of malignant pericardial effusion, J Clin Oncol 3:1678,1985; Maher E, et al: Intraperi-cardial instillation of bleomycin in malignant pericardial effusion, Amer Heart J 11:613,1986; van der Gaast A, et al: Intrapericardial instillation of bleomycin in management of malignant pericardial effusion, Eur J Cancer Clin Oncol 25:1505,1989; Imamura T, et al: Intrapericardial instillation of OK-432 for the management of malignant pericardial effusion, Jpn J Med 28:62,1989, Cormican M, et al: Intraperi-cardial bleomycin for the management of cardiac tamponade secondary to malignant pericardial effusion, Brit Heart J 63:61,1990; Mitchell M, et al: Multiple myeloma complicated by restrictive cardiomyopathy and cardiac tamponade, Chest 103:946, 1993], antineoplastic drugs [Terpenning M, et al: Intrapericardial nitrogen mustard with catheter drainage for the treatment of malignant effusions, Proc Amer Assoc Cancer Res (abstr) 20:286,1979; Markman M, et al: Intrapericardial instillation of cisplatin in a patient with a large malignant effusion, Cancer Drug Delivery 1:49,1985; Figoli F, et al: Pharmacokinetics of VM 26 given intrapericardially or intravenously in patients with malignant pericardial effusion, Cancer Chemotherapy Pharmacol 20:239, 1987; Fiorentino M, et al: Intrapericardial instillation of platin in malignant peri-cardial effusion, Cancer 62:1904,1988], radioactive compound [Martini N, et al: Intra-pericardial instillation of radioactive chronic phosphate in malignant pericardial effusion, AJR 128:639,1977], and a fibrinolytic agent [Cross J, et al: Use of streptokinase to aid in drainage of postoperative pericardial effusion, Brit Heart J 62:217,1989].
Intrapericardial drug delivery has not been clinically utilized for heart-specific treatments where pericardial pathology is normal, because the pericardial space is normally small and very difficult to access without invasive surgery or risk of cardiac injury by standard needle pericardiocentesis techniques. The pericardiocentesis procedure is carried out by experienced personnel in the cardiac catheterization laboratory, with equipment for fluoroscopy and monitoring of the electrocardiogram. Electrocardiographic monitoring of the procedure using the pericardial needle as an electrode is commonly employed [Bishop L H, et al. The electrocardiogram as a safeguard in pericardiocentesis, JAMA 162:264,1956; Neill J R, et al: A pericardiocentesis electrode, N Engl J Med 264:711,1961; Gotsman MS, et al: A pericardiocentesis electrode needle, Br Heart J 28:566,1966; Kerber R E, et al: Electrocardiographic indications of atrial puncture during pericardiocentesis, NEngl JMed 282:1142,1970]. An echocardiographic transducer with a central lumen has also been used to guide the pericardiocentesis needle [Goldberg B B, et al: Ultrasonically guided pericardiocentesis, Amer J Cardiol 31:490,1973]. Complications associated with needle pericardiocentesis include laceration of a coronary artery or the right ventricle, perforation of the right atrium or ventricle, puncture of the stomach or colon, pneumothorax, arrhythmia, tamponade, hypotension, ventricular fibrillation, and death. The complication rates for needle pericardiocentesis are increased in situations where the pericardial space and fluid effusion volume is small (i.e., the pericardial size is more like normal).
Chin et al have described a method and apparatus for accessing the pericardial space for the insertion of implantable defibrillation leads [US. Pat. No. 5,071,428]. The method required gripping the pericardium with a forceps device and cutting the pericardium with a scalpel (pericardiotomy) under direct vision through a subxiphoid surgical incision.
A method for the intrapericardial injection of angiogenic agents has been reported [Uchida Y, et al: Angiogenic therapy of acute myocardial infarction by intrapericardial injection of basic fibroblast growth factor and heparan sulfate, Circulation AHA Abstractsxe2x80x941994]. While the method was not described in detail, it generally involved the percutaneous transcatheter bolus injection of drugs into the pericardial cavity via the right atrium. The major limitation of this method is that the right atrial wall is crossed which could lead to bleeding into the pericardial space. In addition, the method involved the bolus injection of drugs rather than long-term delivery via a catheter or controlled release material.
A principal object of the invention is to provide a method and apparatus for accessing the pericardial space without invasive surgery and to reduce the risk of injury to the heart during pericardial catheterization.
A more specific object of the invention is to provide an apparatus with the means to create a needle puncture through the wall of the pericardium without puncture of the heart.
A further object of the invention is to provide an apparatus with a lumen to be used for the introduction of other elements and materials into the pericardium for site-specific drug delivery to the heart and coronary arteries, or the introduction of implantable defibrillator or other cardioregulatory electrodes into the pericardial space.
Still another object of the invention is to provide a method for advancing a catheter into the pericardial space for the withdrawal of pericardial fluid and/or the intrapericardial injection or infusion of bioactive therapeutic agents to treat diseases of the heart and coronary arteries.
Yet another object of the invention is to provide an apparatus having a simple mode of operation which may be used to pass a guide wire and catheter into the pericardial space without the need for invasive surgery.
The present invention provides apparatus and method for nonsurgical access to the pericardial space through a needle puncture of the anterior pericardium (pericardiocentesis) in a manner reducing risk of injury to the heart, provides a lumen for introduction of substances into the pericardial space through the pierced pericardium, and allows introduction of a catheter into the pericardial space so accessed, thereby to enable the withdrawal of pericardial fluid and/or the intrapericardial injection or infusion of bioactive therapeutic agents to treat diseases of the heart and coronary arteries in a site specific manner, or to allow the introduction of implantable defibrillator electrodes into the pericardial space.
An apparatus of the present invention for percutaneously accessing the intrapericardial space comprises an elongated outer tubular body having a closed distal end, an aperture in a sidewall adjacent the closed end, and a proximal portion for applying a vacuum thereto. An elongated inner tubular body has a distal end sealingly extending into the outer tubular body from a proximal end external to the outer tubular body, creating a first passage between the first and inner tubular bodies. A piercing body is disposed in a distal portion of the outer tubular body adjacent the aperture. The piercing body has a sharp distal end and a lumen extending through it from a proximal end of it to a sidewall opening in it adjacent such sharp distal end. The proximal end of the piercing body is connected to the distal end of the inner tubular body, thereby creating a conduit leading from outside the outer tubular body to the piercing body sidewall opening. The piercing body is longitudinally moveable in the outer tubular body to an extent permitting the distal end of the piercing body to traverse the aperture of the outer tubular body and appose the sidewall opening of the piercing body and the aperture of the outer tubular body. Means providing a passage are laterally adjacent the piercing body for permitting flow communication from the aperture of the outer tubular body to the passage between the tubular bodies, under influence of an applied vacuum, regardless of the longitudinal location of the piercing body in the distal portion of the outer tubular body.
The invention further constitutes a method for accessing a pericardial space, which comprises percutaneously inserting the distal portion of an elongated outer tubular body containing an aperture in a sidewall adjacent the distal end, locating such distal portion over the pericardium substantially parallel thereto with the aperture facing the pericardium surface, applying a vacuum to the tubular body remotely from the distal portion to draw a portion of the pericardium away from the surface of the heart into the aperture in a capture position, advancing a piercing element contained in the tubular body adjacent the aperture in a direction substantially parallel to the heart to pierce the portion of the pericardium captured in the opening, and retracting the piercing element to leave a hole in the pericardium.
The method of this invention further includes delivering a substance through the tubular body and into the pericardial space through the hole created in the pericardium. The substance suitably may be formed or formless. Suitably a formed substance is the distal portion of a filament. The filament may be electro- or photo-conductive, for example, a defibrillator electrode; it may be solid, such as a guidewire; or it may be hollow, such as a catheter. Alternatively the substance may be formless, such as a liquid, paste or gel, and may be bioactive as a cardiovascular drug.
Where the substance is a filament, the method further comprises withdrawing the tubular body and the piercing body over the filament, leaving the filament distal portion in place in the pericardial space with a proximal portion inclusive of the proximal end of the filament remaining external to the body of the patient. Where the filament is electro- or photo-conductive, the invention further comprises accessing the proximal portion of the filament to regulate the heart. Where the filament is hollow, this method thereby provides an indwelling catheter to the pericardial space.
This invention suitably employs an elongated inner tubular body having a distal end sealingly extending into the percutaneously inserted outer tubular body from a proximal end external to the outer tubular body. The piercing element suitably comprises a body having a sharp distal end and a lumen extending therethrough from a proximal end thereof to a sidewall opening therein adjacent such sharp distal end, the proximal end of the piercing body being connected to the distal end of the inner tubular body, thereby creating a conduit leading from externally of the outer tubular body to the piercing body sidewall opening, the piercing body being longitudinally moveable in the outer tubular body to an extent permitting the distal end thereof to traverse the aperture and appose the piercing body sidewall opening and the aperture. In this embodiment, the substance is delivered through the so provided conduit into the pericardial space through the hole created in the pericardium.
In this latter aspect, where the substance is the distal portion of a filament, the step of delivering comprises advancing a filament distal portion through the inner tubular body and through the pericardium portal into the pericardial space. Where the filament is a guidewire, the method of this invention further comprises withdrawing the first and inner tubular bodies and the piercing body over the guidewire, leaving the distal portion of said guidewire in place in the pericardial space, advancing the leading end of a catheter over said guidewire into said pericardial space, and then withdrawing said guidewire to leave said catheter end in said pericardial space. A bioactive substance may then be delivered into the pericardial space through this catheter.
Preferably the distal end of the tubular body is radio-opaque. Suitably the apparatus further comprises an electroconductive terminal adjacent said aperture and a terminal lead electroconductively communicating said terminal exteriorly of outer tubular body remotely from said distal end of said outer tubular body.